I posted to a thread on this subject less than a week ago.
The advantage of side counting aces with hi-lo for shoe games is greater in the UK, where the dealer doesn't take a hole card, and the subsequent ace on a ten will win all doubles and split bets. But I've calculated, very roughly, that the advantage to keeping an ace side count in the UK game (all four and six deck shoes) is marginal - extra work and extra risk of errors for occasional instances where doing so will glean an advantage.
For the US game, where the dealer checks for BJ before anyone plays, I would think the advantage of side-counting aces in shoe games is virtually nil. The only time I canb see it will be of any additional advantage will be in a neg count where there has been a less than expectation number of aces dealt out. A greater chance of BJ's but where normally a minimum bet will be made. In this case, deviating from a normal betting ramp is justified, although if kelly betting you would have to calculate the %age advantage - which will change dependent on the neg TC and number of aces still left in the shoe. As I said before, I think all this is tweaking at the edges.
Anyone from the other side of the pond care to comment?